Fractionating and condensing unit



March 9, 1937. J. s. WALLIS 2,073,258

FRACTIONATING AND GONDENSING UNIT Filed dot. 22, 1952 By 7145. aw V ATTORNEY.

Patented Mar. 9, 1937.

UNITED STATES PATENT orrlcs Products, Inc., New York, N.

of Delaware Y., a corporation Application October 22, 1932, Serial No. 639,077

8 Claims. My invention relates to a fractions-ting and condensing unit, and more particularly to a.

combination unit for use with the processing of hydrocarbon oils adapted to combine in a single unit the functions of a fractionating tower and 1 of a condenser.

In the construction known to the art, it is customary to heat a hydrocarbon oil to vaporizing temperature and fractionate it into constituents having different boiling point ranges in a fractionating tower of any suitable design. The uncondensed vapors are withdrawn overhead from the fractionating towers of the prior art and passed to condensers for cooling. It has been developed that fractionation under a vacuum will assist in removing the lighter constituents in a fractionating tower. When fractionation is practiced under a vacuum, the vapors must be condensed under a vacuum. This makes it necessary to keep both the condenser and the fractionating tower under a reduced pressure. While I have mentioned the vacuum fractionation, it is to be understood that my invention hereinafter described is not to be limited to a vacuum operation but may be used in any desired process, the invention being directed chiefly to the construction of my unit.

One of the objects of my invention is to provide a combined fractionating and condensing unit which will perform the work of two individual units as now employed in the art, with a consequent reduction in space and in the cost of construction. I

Other objects of my invention will appear from the following description. v

In the accompanying drawing which forms a part of the instant specification and. which is to be read in conjunction therewith;

Figure 1 shows a sectional view of the unit embodying one method of carrying out my invention. I

,Figure 2 is a sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a sectional view tak'enon the line 3--3 of Figure 1. 4

Figure 4 is a sectional view taken on the line I fractionating decks 2, 3, 4, etc. may be provided 4--4 of Figure 3.

Referring now to the drawing, the tower is formed with a casing I of 'any suitable construction and is provided with a plurality of fractionating decks 2, 3, 4, and 5. It is to be understood that any suitable number of these fractionating decks may be provided. The fractionating decks may be of any suitable construction, thedrawing showing a trough construction in which vapors bubble through the liquid which collects in the troughs. The liquid is permitted to overflow and course downwardly through the tower. Astripping section 8 is provided in my tower. While I have shown but one stripping section, it is to be understood that any num ;ber of stripping sections may be employed at. suitable places.

vided with a perforated steam distributing pipe The stripping section is pro- 1 which is fed through pipe 8. The steam emerging through holes in pipe 1 strips the product passing through the stripping section of its lighter constituents. The stripping section is provided with a pipe 9 through which steam liberated in the stripping section is returned to the point of flash. A pipe I0 is connected to a heater of any suitable design and conducts the oil heated to vaporization temperature to the tower l, entering through any suitable opening ll. Immediately above the opening II are a plurality of baiiie plates l2. These baille plates may be of any suitable construction. In the lower part of the tower, I provide a Perforated pipe l3 which is fed by steam through line l4. The function of the pipe l3 isto permit steam to emerge from the perforations thereof to strip the residue collecting in the lower part of the tower l5 of its lighter constituents. The part of the tower which is described constitutes the fractionating part of my unit. The vapors which will be composed of hydrocarbon fractions having lower boiling point ranges will pass the uppermost deck 2 in the form of vapors through passages 20 and 2| formed by a housing I1 with the casing I as shown by the arrows in Figure 1. The Vapors rising through passages 20 and 2| will reach the partition 22 and be deflected downwardly in contact with the cooling bank 23 of the condenser 24. This condenser may be of any suitable construction. It is provided with pipes 25 and 28 through which cooling water is fed through the tube bank 23. The light hydrocarbon vapors coursing downwardly in contact with the cool tubes will have a part of the constituents thereof condensed. The condensate will collect in receiver 30. Receiver 30 is provided with a. withdrawal pipe 3| through which the condensate is withdrawn. Likewise, an overflow pipe 32 is provided for refluxing a portion of the condensate to the uppermost fractionating deck 2. It is to be understood that the with drawoifs for withdrawing the fractions which collect thereon, as for example, the pipe 28 which is fitted in the stripping section 6 for withdrawing the stripped product therefrom.

The uncondensed vapors and incondensable gases will pass upwardly through conduits 40,

4!, 42, and 43 as can be seen by reference to Figures 3 and 4. These gases and vapors must pass -in contact with additional condensing means provided at the uppermost part of the tower. A plurality of decks 50, 5|, 52, and 53 are provided. These decks have suitable perforations such as $4, 55, and 58 permitting liquid on one of the decks to pass to the deck below. The lower decks are provided with apertures having flanges therearound to govern depth of the liquid on the decks 50, and-52. Water through pipe 51 is discharged on the upper deck," and courses downwardly, collecting on the lower decks, and overflowing as can be readily seen by reference to-Figure 1.

. Uncondensed vapors and incondensable gases pass upwardly through the spray or rainof wa- 1 tower terminates in a 0 passes downwardly through lines I5 and 18 to the hot well 62. The barometric condenser using steam jets is well known in the art and any suitable type may be used. It is to be understood that, while I have shown the steam jets as a means of keeping my unit under reduced pressure, that I may eliminate the vacuum maintaining means if an atmospheric distillation operation is desired.

In operation, the oil vapors heated to vaporizing temperature in a still or any suitable apparatus, enter my unit through line Ill. The heated oil flashes into vapors after leaving inlet II. The vapors course upwardly through my unit and condense on the various decks of the fractionating portion of the tower, according to the boiling point ranges thereof. The fractions which collect on the decks will overflow and course downwardly through the tower. A portion of this downwardly coursing condensate may be stripped in suitable stripping sections. The lighter vapors pass upwardly and are condensedin my condensing section. The uncondensed vapors are cooled by contact witha cooling medium and are withdrawn by means of barometric condensers or any suitable vacuum means. It is believed that the operation will be clear from the foregoing description.

It will be understood that certain features and sub-combinations are of utility and may be employed without reference to other features and sub-combinations. This is contemplated by and is within the scope of my claims. It is further obvious-that, various changes may be made in details within the scope of my claims without departing from the spirit of my invention. It is, therefore, to be understood that my invention is not to be limited to the specific details shown and described.

Having thus described my invention, what-I claim is:

1. A fractionating and condensing unit comprising in combination a casing, a plura1ity of fractionating decks extending across said casing, a housing mounted within said casing above the uppermost oi said'decks, a partition extending across said casing above and spaced from said housing, condensing means mounted within said housing, 'a condensate receiving means mounted below, said condensing means, a duct leading from said housing through said partition for leading the uncondensed vapors above said partition, a connection. for introducing heat-v,

ed vapors into the casing and a connection for withdrawing the condensate.

I maintaining said 2. A fractionating and condensing unit com prising in combination a casing, a plurality of fractionating decks extending across said casing in spaced relation to each other, said decks being provided with openings for the passage of vapors therethrougma housing mounted within said casing above said decks, the upper portion of said housing being provided with an opening for the passage of vapors thereinto, condenser tubes positioned in the upper portion of said housing adapted to condense a portion of the vapors, the lower portion of said housing being free of tubes and adapted to collect the condensate, means for withdrawing the uncondensed vapors and incondensable gases from said housing and means for withdrawing the condensate.

3. A unit as in claim 2 including means mounted within said casing for directly contacting the uncondensed vapors withdrawn from said housing with a cooling medium.

4. A ,fractionating and condensing unit comprising in combination a casing, a plurality of fractionating decks extending across said casing in spaced relation to each other, said decks being provided with openings for the passage of vapors therethrough, a housing mounted within said casing above .the uppermost of saidfractionating decks, the upper portion of said housing being provided with an opening for the passage of vapors thereinto, condenser tubes positioned in the upper portion of said housing adapted to condense a portion of the vapors, the lower portion of said housing being free of tubes and adapted to collect the condensate, means for withdrawing the uncondensed vapors and incondensable gases from said housing and means for withdrawing the condensate, and an overflow means communicating with said housing for per: mitting a portion of the condensate to flow to the highest fractionating deck after a predetermined level of condensate has been reached within said housing.

5. A unit as in claim 2 including means for maintaining said casing under sub-atmospheric pressure.

6. A unit as in claim 4 including means for casing under sub-atmospheric pressure. p r

7. A fractionating tower including in combination a shell, a plurality of fractionating decks .within said shell, a housing mounted within said shell above said decks and spaced from the interior surfaces thereof to form a vapor passage, said housing being provided with an opening communicating with said passage and in the upper portion of said housing, a condenser positioned in the upper portion of said housing, the lower portion of said housing being free of tubes and forming a condensate receiver, a condensate drawofi line from said receiver and a duct communicating with said housing for withdrawing uncondensed vapors therefrom.

8. In a fractionating tower a' partition extending across the interior thereof, a housing suspended from said partition and mounted in spaced relation with the interior walls of the fractionating tower to form a vapor passage, a vapor inlet from said passage into the upper portion of said housing, a condenser mounted in said housing, and means forming a duct extending from said housing below said condenser through said partition for conducting uncondensed vapors thereabove. 7

JOHN S. WALLIS. 

